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| Concern Voiced Over Solar Inactivity |
385 Views |
| posted on Thursday, June 12, 2008 |
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THE SUNSPOT ENIGMA: THE SUN IS “DEAD” -- WHAT DOES IT MEAN FOR EARTH?
By Rebecca Sato
Daily Galaxy
June 11, 2008
Original Link
Dark spots, some as large as 50,000 miles in diameter, typically move across the surface of the sun, contracting and expanding as they go. These strange and powerful phenomena are known as sunspots, but now they are all gone. Not even solar physicists know why it’s happening and what this odd solar silence might be indicating for our future.
Although periods of inactivity are normal for the sun, this current period has gone on much longer than usual and scientists are starting to worry -- at least a little bit. Recently 100 scientists from Europe, Asia, Latin America, Africa and North America gathered to discuss the issue at an international solar conference at Montana State University. Today's sun is as inactive as it was two years ago, and solar physicists don’t have a clue as to why.
"It continues to be dead," said Saku Tsuneta with the National Astronomical Observatory of Japan, program manager for the Hinode solar mission, noting that it is at least a little bit worrisome for scientists.
Dana Longcope, a solar physicist at MSU, said the sun usually operates on an 11-year cycle with maximum activity occurring in the middle of the cycle. The last cycle reached its peak in 2001 and is believed to be just ending now, Longcope said. The next cycle is just beginning and is expected to reach its peak sometime around 2012. But so far nothing is happening.
"It's a dead face," Tsuneta said of the sun's appearance.
Tsuneta said solar physicists aren't weather forecasters and they can't predict the future. They do have the ability to observe, however, and they have observed a longer-than-normal period of solar inactivity. In the past, they observed that the sun once went 50 years without producing sunspots. That period coincided with a little ice age on Earth that lasted from 1650 to 1700. Coincidence? Some scientists say it was, but many worry that it wasn’t.
Geophysicist Phil Chapman, the first Australian to become an astronaut with NASA, said pictures from the US Solar and Heliospheric Observatory also show that there are currently no spots on the sun. He also noted that the world cooled quickly between January last year and January this year, by about 0.7C.
"This is the fastest temperature change in the instrumental record, and it puts us back to where we were in 1930," Dr Chapman noted in The Australian today.
If the world does face another mini Ice Age, it could come without warning. Evidence for abrupt climate change is readily found in ice cores taken from Greenland and Antarctica. One of the best known examples of such an event is the Younger Dryas cooling, which occurred about 12,000 years ago, named after the arctic wildflower found in northern European sediments. This event began and ended rather abruptly, and for its entire 1000 year duration the North Atlantic region was about 5°C colder. Could something like this happen again? There’s no way to tell, and because the changes can happen all within one decade -- we might not even see it coming.
The Younger Dryas occurred at a time when orbital forcing should have continued to drive climate to the present warm state. The unexplained phenomenon has been the topic of much intense scientific debate, as well as other millennial scale events.
Now this 11-year low in Sunspot activity has raised fears among a small but growing number of scientists that rather than getting warmer, the Earth could possibly be about to return to another cooling period. The idea is especially intriguing considering that most of the world is in preparation for global warming.
Canadian scientist Kenneth Tapping of the National Research Council has also noted that solar activity has entered into an unusually inactive phase, but what that means -- if anything -- is still anyone’s guess. Another solar scientist, Oleg Sorokhtin, a fellow of the Russian Academy of Natural Sciences, however, is certain that it’s an indication of a coming cooling period.
Sorokhtin believes that a lack of sunspots does indicate a coming cooling period based on certain past trends and early records. In fact, he calls manmade climate change "a drop in the bucket" compared to the fierce and abrupt cold that can potentially be brought on by inactive solar phases.
Sorokhtin’s advice: "Stock up on fur coats"…just in case.
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SUN GOES LONGER THAN NORMAL WITHOUT PRODUCING SUNSPOTS
ScienceDaily
June 9, 2008
Original Link
The sun has been lying low for the past couple of years, producing no sunspots and giving a break to satellites.
That's good news for people who scramble when space weather interferes with their technology, but it became a point of discussion for the scientists who attended an international solar conference at Montana State University. Approximately 100 scientists from Europe, Asia, Latin America, Africa and North America gathered June 1-6 to talk about "Solar Variability, Earth's Climate and the Space Environment."
The scientists said periods of inactivity are normal for the sun, but this period has gone on longer than usual.
"It continues to be dead," said Saku Tsuneta with the National Astronomical Observatory of Japan, program manager for the Hinode solar mission. "That's a small concern, a very small concern."
The Hinode satellite is a Japanese mission with the United States and United Kingdom as partners. The satellite carries three telescopes that together show how changes on the sun's surface spread through the solar atmosphere. MSU researchers are among those operating the X-ray telescope. The satellite orbits 431 miles above ground, crossing both poles and making one lap every 95 minutes, giving Hinode an uninterrupted view of the sun for several months out of the year.
Dana Longcope, a solar physicist at MSU, said the sun usually operates on an 11-year cycle with maximum activity occurring in the middle of the cycle. Minimum activity generally occurs as the cycles change. Solar activity refers to phenomena like sunspots, solar flares and solar eruptions. Together, they create the weather than can disrupt satellites in space and technology on earth.
The last cycle reached its peak in 2001 and is believed to be just ending now, Longcope said. The next cycle is just beginning and is expected to reach its peak sometime around 2012. Today's sun, however, is as inactive as it was two years ago, and scientists aren't sure why.
"It's a dead face," Tsuneta said of the sun's appearance.
Tsuneta said solar physicists aren't like weather forecasters; They can't predict the future. They do have the ability to observe, however, and they have observed a longer-than-normal period of solar inactivity. In the past, they observed that the sun once went 50 years without producing sunspots. That period, from approximately 1650 to 1700, occurred during the middle of a little ice age on Earth that lasted from as early as the mid-15th century to as late as the mid-19th century.
Tsuneta said he doesn't know how long the sun will continue to be inactive, but scientists associated with the Hinode mission are ready for it to resume maximum activity. They have added extra ground stations to pick up signals from Hinode in case solar activity interferes with instruments at other stations around the world. The new stations, ready to start operating this summer, are located in India, Norway, Alaska and the South Pole.
Establishing those stations, as well as the Hinode mission, required international cooperation, Tsuneta said. No one country had the resources to carry out those projects by itself.
Four countries, three space agencies and 11 organizations worked together on Hinode which was launched in September 2006, Tsuneta said. Among the collaborators was Loren Acton, a research professor of physics at MSU. Tsuneta and Acton worked together closely from 1986-2002 and were reunited at the MSU conference.
"His leadership was immense, superb," Tsuneta said about Acton.
Acton, 72, said he is still enthused by solar physics and the new questions being raised. In fact, he wished he could knock 22 years off his age and extend his career even longer.
"It's too much fun," he said. "There's so much exciting stuff come up, I would like to be part of it."
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NHNE Climate Change Resource Page
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